anatomical structure organ heart A myogenic muscular circulatory organ found in the vertebrate cardiovascular system composed of chambers of cardiac muscle. It is the primary circulatory organ. AAO:0010210 As noted, the hearts of birds and mammals have four chambers that arises from the two chambers (atrium and ventricle) of the fish heart.[well established][VHOG] BILA:0000020 BTO:0000562 Blood pumping organ composed of four chambers: sinus venosus, atrium, cardiac ventricle and bulbus arteriosus.[TAO] CALOHA:TS-0445 EFO:0000815 EHDAA2:0000738 EHDAA:420 EMAPA:16105 EV:0100018 FMA:7088 GAID:174 Herz@de MA:0000072 MAT:0000036 MESH:D006321 MIAA:0000036 OpenCyc:Mx4rvVjvDpwpEbGdrcN5Y29ycA Part of the circulatory system responsible for pumping blood; composed of three chambers--two atria and one ventricle.[AAO] TAO:0000114 Taxon notes:" the ascidian tube-like heart lacks chambers....The ascidian heart is formed after metamorphosis as a simple tube-like structure with a single-layered myoepithelium that is continuous with a single-layered pericar- dial wall. It lacks chambers and endocardium.... The innovation of the chambered heart was a key event in vertebrate evolution, because the chambered heart generates one-way blood flow with high pressure, a critical requirement for the efficient blood supply of large-body vertebrates... all extant vertebrates have hearts with two or more chambers (Moorman and Christoffels 2003)" http://dx.doi.org/10.1101/gad.1485706 UBERON:0000948 UMLS:C0018787 VHOG:0000276 XAO:0000064 ZFA:0000114 branchial heart cardiac cardium chambered heart doid.owl galen:Heart obi.owl relationship type change: differentiates_from lateral plate mesoderm (AAO:0010574) CHANGED TO: develops_from lateral plate mesoderm (UBERON:0003081)[AAO] uberon vertebrate heart mesoderm-derived structure trunk region element